/***************************************************************************************************
  *Copyright(C),2010-2016,Sumscope
  *FileName	:  base64.cpp
  *Author	:  scofined.qi
  *Version	:  1.0
  *Date		:  2016/01/28
  *Desc		:  //用于主要说明此程序文件完成的主要功能
  *Relation :  
  *Others	:  //其他内容说明
  *Function :  //主要函数列表，每条记录应包含函数名及功能简要说明
  *History	:  //修改历史记录列表，每条修改记录应包含修改日期、修改者及修改内容简介
***************************************************************************************************/
#include "base64.h"

//#ifdef _DEBUG
//#define new DEBUG_NEW
//#endif

namespace qb{
	namespace base{


		///////////////////////////////////////////////////////////////////////////////////
		/// The usefull base64 encoder and decoder

#define MAXLINE  76

		/*============================================================================
		* Everything below this line is private to this file (static)
		*============================================================================
		*/

		static char base64tab[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
			"abcdefghijklmnopqrstuvwxyz0123456789+/";

		static char base64idx[128] = {
			'\377','\377','\377','\377','\377','\377','\377','\377',
			'\377','\377','\377','\377','\377','\377','\377','\377',
			'\377','\377','\377','\377','\377','\377','\377','\377',
			'\377','\377','\377','\377','\377','\377','\377','\377',
			'\377','\377','\377','\377','\377','\377','\377','\377',
			'\377','\377','\377',    62,'\377','\377','\377',    63,
			52,    53,    54,    55,    56,    57,    58,    59,
			60,    61,'\377','\377','\377','\377','\377','\377',
			'\377',     0,     1,     2,     3,     4,     5,     6,
			7,     8,     9,    10,    11,    12,    13,    14,
			15,    16,    17,    18,    19,    20,    21,    22,
			23,    24,    25,'\377','\377','\377','\377','\377',
			'\377',    26,    27,    28,    29,    30,    31,    32,
			33,    34,    35,    36,    37,    38,    39,    40,
			41,    42,    43,    44,    45,    46,    47,    48,
			49,    50,    51,'\377','\377','\377','\377','\377'
		};

		static char hextab[] = "0123456789ABCDEF";
		static char eol_string[] = "\r\n";

#ifdef __cplusplus
		inline int isbase64(int a) {
			return ('A' <= a && a <= 'Z')
				|| ('a' <= a && a <= 'z')
				|| ('0' <= a && a <= '9')
				|| a == '+' || a == '/';
		}
#else
#define isbase64(a) (  ('A' <= (a) && (a) <= 'Z') \
	|| ('a' <= (a) && (a) <= 'z') \
	|| ('0' <= (a) && (a) <= '9') \
	||  (a) == '+' || (a) == '/'  )
#endif


		int Base64::Encode(const char* aIn, size_t aInLen, char* aOut,
			size_t aOutSize, size_t* aOutLen)
		{
			size_t inLen = 0;
			char* out = 0;
			size_t outSize = 0;
			size_t inPos = 0;
			size_t outPos = 0;
			int c1, c2, c3;
			int lineLen = 0;
			size_t i;
			const char *cp = 0;


			if (!aIn || !aOut || !aOutLen)
				return -1;
			inLen = aInLen;
			out = aOut;
			outSize = (inLen+2)/3*4;     /* 3:4 conversion ratio */
			outSize += strlen(eol_string)*outSize/MAXLINE + 2;  /* Space for newlines and NUL */
			if (aOutSize < outSize)
				return -1;

			/* Get three characters at a time and encode them. */
			for (i=0; i < inLen/3; ++i) {
				c1 = aIn[inPos++] & 0xFF;
				c2 = aIn[inPos++] & 0xFF;
				c3 = aIn[inPos++] & 0xFF;
				out[outPos++] = base64tab[(c1 & 0xFC) >> 2];
				out[outPos++] = base64tab[((c1 & 0x03) << 4) | ((c2 & 0xF0) >> 4)];
				out[outPos++] = base64tab[((c2 & 0x0F) << 2) | ((c3 & 0xC0) >> 6)];
				out[outPos++] = base64tab[c3 & 0x3F];
				lineLen += 4;
				if (lineLen >= MAXLINE-3) {
					cp = eol_string;
					out[outPos++] = *cp++;
					if (*cp) {
						out[outPos++] = *cp;
					}
					lineLen = 0;
				}
			}
			/* Encode the remaining one or two characters. */
			switch (inLen % 3) {
	case 0:
		cp = eol_string;
		out[outPos++] = *cp++;
		if (*cp) {
			out[outPos++] = *cp;
		}
		break;
	case 1:
		c1 = aIn[inPos] & 0xFF;
		out[outPos++] = base64tab[(c1 & 0xFC) >> 2];
		out[outPos++] = base64tab[((c1 & 0x03) << 4)];
		out[outPos++] = '=';
		out[outPos++] = '=';
		cp = eol_string;
		out[outPos++] = *cp++;
		if (*cp) {
			out[outPos++] = *cp;
		}
		break;
	case 2:
		c1 = aIn[inPos++] & 0xFF;
		c2 = aIn[inPos] & 0xFF;
		out[outPos++] = base64tab[(c1 & 0xFC) >> 2];
		out[outPos++] = base64tab[((c1 & 0x03) << 4) | ((c2 & 0xF0) >> 4)];
		out[outPos++] = base64tab[((c2 & 0x0F) << 2)];
		out[outPos++] = '=';
		cp = eol_string;
		out[outPos++] = *cp++;
		if (*cp) {
			out[outPos++] = *cp;
		}
		break;
			}
			out[outPos] = 0;
			*aOutLen = outPos;
			return 0;
		}

		int Base64::Decode(const char* aIn, size_t aInLen, char* aOut,
			size_t aOutSize, size_t* aOutLen)
		{
			size_t inLen = 0;
			char * out = 0;
			size_t outSize = 0;

			int isErr = 0;
			int isEndSeen = 0;
			int b1, b2, b3;
			int a1, a2, a3, a4;
			size_t inPos = 0;
			size_t outPos = 0;

			if (!aIn || !aOut || !aOutLen)
				return -1;
			inLen = aInLen;
			out = aOut;
			outSize = (inLen+3)/4*3;
			if (aOutSize < outSize)
				return -1;
			/* Get four input chars at a time and decode them. Ignore white space
			* chars (CR, LF, SP, HT). If '=' is encountered, terminate input. If
			* a char other than white space, base64 char, or '=' is encountered,
			* flag an input error, but otherwise ignore the char.
			*/
			while (inPos < inLen) {
				a1 = a2 = a3 = a4 = 0;
				while (inPos < inLen) {
					a1 = aIn[inPos++] & 0xFF;
					if (isbase64(a1)) {
						break;
					}
					else if (a1 == '=') {
						isEndSeen = 1;
						break;
					}
					else if (a1 != '\r' && a1 != '\n' && a1 != ' ' && a1 != '\t') {
						isErr = 1;
					}
				}
				while (inPos < inLen) {
					a2 = aIn[inPos++] & 0xFF;
					if (isbase64(a2)) {
						break;
					}
					else if (a2 == '=') {
						isEndSeen = 1;
						break;
					}
					else if (a2 != '\r' && a2 != '\n' && a2 != ' ' && a2 != '\t') {
						isErr = 1;
					}
				}
				while (inPos < inLen) {
					a3 = aIn[inPos++] & 0xFF;
					if (isbase64(a3)) {
						break;
					}
					else if (a3 == '=') {
						isEndSeen = 1;
						break;
					}
					else if (a3 != '\r' && a3 != '\n' && a3 != ' ' && a3 != '\t') {
						isErr = 1;
					}
				}
				while (inPos < inLen) {
					a4 = aIn[inPos++] & 0xFF;
					if (isbase64(a4)) {
						break;
					}
					else if (a4 == '=') {
						isEndSeen = 1;
						break;
					}
					else if (a4 != '\r' && a4 != '\n' && a4 != ' ' && a4 != '\t') {
						isErr = 1;
					}
				}
				if (isbase64(a1) && isbase64(a2) && isbase64(a3) && isbase64(a4)) {
					a1 = base64idx[a1] & 0xFF;
					a2 = base64idx[a2] & 0xFF;
					a3 = base64idx[a3] & 0xFF;
					a4 = base64idx[a4] & 0xFF;
					b1 = ((a1 << 2) & 0xFC) | ((a2 >> 4) & 0x03);
					b2 = ((a2 << 4) & 0xF0) | ((a3 >> 2) & 0x0F);
					b3 = ((a3 << 6) & 0xC0) | ( a4       & 0x3F);
					out[outPos++] = (char)(b1);
					out[outPos++] = (char)(b2);
					out[outPos++] = (char)(b3);
				}
				else if (isbase64(a1) && isbase64(a2) && isbase64(a3) && a4 == '=') {
					a1 = base64idx[a1] & 0xFF;
					a2 = base64idx[a2] & 0xFF;
					a3 = base64idx[a3] & 0xFF;
					b1 = ((a1 << 2) & 0xFC) | ((a2 >> 4) & 0x03);
					b2 = ((a2 << 4) & 0xF0) | ((a3 >> 2) & 0x0F);
					out[outPos++] = (char)(b1);
					out[outPos++] = (char)(b2);
					break;
				}
				else if (isbase64(a1) && isbase64(a2) && a3 == '=' && a4 == '=') {
					a1 = base64idx[a1] & 0xFF;
					a2 = base64idx[a2] & 0xFF;
					b1 = ((a1 << 2) & 0xFC) | ((a2 >> 4) & 0x03);
					out[outPos++] = (char)(b1);
					break;
				}
				else {
					break;
				}
				if (isEndSeen) {
					break;
				}
			} /* end while loop */
			*aOutLen = outPos;
			return (isErr) ? -1 : 0;
		}


		int Base64::Encode(const  BaseString &strSrc, BaseString &strDest )
		{
			size_t destSize = 4*(strSrc.size()+2)/3;
			destSize += strlen("\r\n")*destSize/72 + 2;
			destSize += 64; /*64;  a little extra room */

			/* Allocate destination buffer */
			// OPTIMIZE:使用StackArray可以提高性能,see PipeMessagePtr::PipeMessagePtr
			char * destBuf = new char[destSize];//strDest.GetBuffer(destSize);
			if( 0 == destBuf )
			{
				//strDest.ReleaseBuffer();
                return 0;
			}

			/* Encode source to destination */
			size_t destLen = 0;
			int result = Encode(strSrc.c_str(), strSrc.size(), destBuf, destSize, &destLen);
			if( destLen < destSize )
				destBuf[destLen]	=	'\0';

			//strDest.ReleaseBuffer();
			strDest = destBuf;
			if(destBuf) delete []destBuf;
			return strDest.size();
		}

		int Base64::Decode(const BaseString &strSrc, BaseString &strDest )
		{
			size_t destSize = 4*(strSrc.size()+2)/3;
			destSize += strlen("\r\n")*destSize/72 + 2;
			destSize += 64; /*64;  a little extra room */

			/* Allocate destination buffer */
			// OPTIMIZE:使用StackArray可以提高性能,see PipeMessagePtr::PipeMessagePtr
			char * destBuf =  new char[destSize];//strDest.GetBuffer(destSize);
			if( 0 == destBuf )
			{
				//strDest.ReleaseBuffer();
                return 0;
			}

			/* Encode source to destination */
			size_t destLen = 0;
			int result = Decode(strSrc.c_str(), strSrc.size(), destBuf, destSize, &destLen);
			if( destLen < destSize )
				destBuf[destLen]	=	'\0';

			strDest = destBuf;
			if(destBuf) delete [] destBuf;
			return strDest.size();
		}

		//////////////////////////////////////////////////////////////////////////
		// CRC32 and CRC16

		static unsigned int crc_32_tab[] = {
			0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
			0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
			0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
			0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
			0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
			0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
			0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
			0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
			0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
			0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
			0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
			0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
			0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
			0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
			0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
			0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
			0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
			0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
			0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
			0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
			0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
			0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
			0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
			0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
			0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
			0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
			0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
			0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
			0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
			0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
			0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
			0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
			0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
			0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
			0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
			0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
			0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
			0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
			0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
			0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
			0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
			0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
			0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
			0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
			0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
			0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
			0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
			0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
			0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
			0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
			0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
			0x2d02ef8dL
		};

		unsigned int Base64::CRC32(const char *s, int len)
		{
			register unsigned c;
			unsigned int crc = (unsigned int)0xffffffffL;

			if (s == 0)
			{
				c = 0xffffffffL;
			}
			else
			{
				c = crc;
				if(len)
				{
					do
					{
						c = crc_32_tab[((int)c ^ (*s++)) & 0xff] ^ (c >> 8);
					} while (--len);
				}
			}
			crc = c;
			return c ^ 0xffffffffL;
		}

        unsigned short Base64::CRC16(const unsigned char *info, unsigned long len)
		{ 
            unsigned short acc;
			unsigned char i;
			acc=0;
			while( len-- )
			{
				acc=acc^(((unsigned int)(*info))<<8);
				info++;
				for( i=8; i>0; i-- )
				{
					if (acc&0x8000)
						acc=(acc<<1)^0x1021;
					else acc<<=1; 
				}
			} 
			return acc; 
		} 

	}
}


